Documented information of external origin during the certification audit

what other ISO standards should be available in my office while the certification body is auditing'

Answer:
You should have at list a paper or electronic copy of ISO 9001:2015. You should also have paper or electronic copies of standards that are relevant for the quality of your product or service. Those determined under clause 7.5.3.2 as documented information of external origin.

The following material will provide you more information about documented information of external origin:
What does “external documents control” mean in ISO 9001? - https://advisera.com/9001academy/blog/2019/02/04/what-does-external-documents-control-mean-in-iso-9001/
Enroll for free in this course – ISO 9001:2015 Foundations Course - https://advisera.com/training/iso-9001-foundations-course/
- Book – Discover ISO 9001:2015 Through Practical Examples – https://advisera.com/books/discover-iso-9001-2015-through-practical-examples/